Process of recovering rosin from rosin-containing soap produced in the manufacture of paper pulp from rosin-containing wood



\ by regeneration.

cover the rosin, the soaps being destroyed in Patented Nov. 22, 1932 UNITED STATES PATENT. OFFICE LEAVITT N. BENT, O1 HOLLY OAK, DELAWARE, ASSIGNO R TO HERCULES POWDER COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION OF DELAWARE PROCESS OF RECOVERING ROSIN FROM ROSIN-CONTAINING SOAP PRODUCED IN THE MANUFACTURE OF PAPER PULP FROM ROSIN-CONTAINING WOOD No Drawing. Application filed May 25, 1927. Serial No. 194,239.

In the manufacture of paper pulp, by the a day, at ordinary temperature, at the end of soda process or the so-called sulphate process, which time ractically all the rosin will have from wood chips containing rosins, the rosins settled; or t e solution may be heated for a are separated by the alkaline liquor and short time so that the rosin coagulates to a form dark colored rosin soaps, which float solid mass, from which the liquor may be on the surface of the recovered 1i uid asa drawn ofi. scum or froth, which is skimmed o It has The thus recovered rosin amounts to about been proposed to precipitate the rosin from 150 parts of a soft rosin having an acid numthis soap by the use of hydrochloric acid, bcr of 150. While somewhat darker in color sulfuric acid or nitre cake, but such of these than average commercial wood rosin, under processes'as are satisfactorily operative are similar conditions it will give a soap of about so expensive that they have not gone into the same color as can be obtained-from such successful commercial use, and it is custocommercial wood rosin, which soap shows mary, therefore, to make no attempt to relittle discoloration with age.

One hundred parts of the above soft rethe heat treatment to recover the alkali salts covered rosin was, fractionally distilled undcr one half inch pressure of mercury and the The object-of my invention is to treat the following cuts obtaine v soaps for recovery of the rosin in marketable condition by a process that is so inexpensive Saponmca that the value of the rosin w1ll greatly exceed Quantity Acid tion No. thecost of recovery. A supplementary object of the invention is to provide a rosing? 160 1 recovery process that Wlll perm1t of the re- -IIII.'I1111"'IIIII 22 172 11s covery of the alkali salts as well as the 55555 13111 t3 rosin. L088 3 Examples of ways of practicing my pro- 065s W111 descnbed- Because of the presence of rosin oil, out No. T TOSPI p cobtalnmg more less 1 was rather soft. The second cut was also molstule, 1S dlssolyed 111 Water- The amount slightly softer than ordinary distilled rosin.

- of Water added will depend p the Chat" The hardness of these cuts may be improved actel b P- In exceptlonal lnstancesa by distilling from a still having a fractionatthe addlffilon 0f P y not be necessary ing column and making a preliminary cut in In a yp QPeTatlOn, 300 Parts of the which the rosin oil is concentrated, leaving a p contalblng abollt 30 P centof rosin remainder of as high a quality as the ture, w dlssolyed In 2700 b b 9 w higher commercial grades of wood rosin and A rapld current of Car n dIOXKl 1S p f giving soaps similar to those obtained from t g the sollltlon (P y y bllbbhbg gum rosins or similar grades of rosin. 1t through l fi l about My process is commercially practicable bel1 11 B P -mp the IOSm y the cause of the inexpensiveness of the treating bon d1 X1 1 y i f o ple e-, agent, which may be obtained from flue gases; pletl n f h recl ltationzm rb i rsiMy process is further advantageous and ecommed bv rem vlng a samp a t g y nomical because of the use of carbon dioxid addlng dilute sulfurlc acid. leaves the sodium salts from which the rosin The IOSlIl, which 1s m a finely div ded state, is separated in the form of sodium carbonate, may be separated from the water in various which is easy and cheap to recover in the ways. It may be extracted with a low boiling paper pulp plant. hydrocarbon, such as gasoline, benzol or In specifying that the rosin is precipitated other rosin solvent immiscible with water; or by the carbon dioxid, I mean it to be nderthe solution may be allowed to stand for about stood that the rosin is so separated in solid form from the salt solution that it is capable Y of being recovered by means of a solvent immiscible with water, or by coagulation, or in any other known way of separating rosin from a salt solution.

" Having now fully described my invention, what I claim and desire to protect by Letters Patent is:

1. The process of recovering vrosin from rosin soaps of the character of those produced in the manufacture of paper pulp from rosincontaining wood, which comprises recipitating the rosin by means of carbon 'oxid, and separating out the rosin.

2. The process of recovering rosin from rosin soaps of the character of those produced in the manufacture of paper pulp from rosincontaining wood, which comprises adding water and precipitating the rosin by passing through the soap solution carbon dioxid, and separating out the rosin.

3. The process of recovering rosin from soaps, containing rosin, alkali salts and water, of the character of those formed in the manufacture of paper pulp from rosin-containing wood, which comprises percipitating rosin and converting the salts to carbonates by passing through the soap solution carbon dioxid. y

In testimony of which invention, I have hereunto set my hand, at Wilmington, Del.,

on this 21st day ofMay, 1927.

LEAV ITT N. BENT. 

